Focal adhesion tyrosine kinase (PTK2) is a cytoplasmic protein tyrosine kinase. PTK2 plays an important role in adhesion, spreading, motility, invasion, metastasis, survival, angiogenesis, epithelial to mesenchymal transition, cancer stem cells, and the tumor microenvironment. Overexpression and activation of PTK2 connect with several human malignant diseases, including colorectal, ovarian,...